diff --git a/src/sql/code_generator/ob_code_generator_impl.cpp b/src/sql/code_generator/ob_code_generator_impl.cpp
index 22d26d091157b7e7a4335ec6f53b10a97e981723..1bf49516b9efc3e197eee42c8a393205f61cef3d 100644
--- a/src/sql/code_generator/ob_code_generator_impl.cpp
+++ b/src/sql/code_generator/ob_code_generator_impl.cpp
@@ -9170,16 +9170,17 @@ int ObCodeGeneratorImpl::get_cell_idx(
   if (OB_ISNULL(raw_expr)) {
     ret = OB_ERR_UNEXPECTED;
     LOG_WARN("Get unexpected null", K(ret));
-  } else if (!raw_expr->has_flag(IS_COLUMNLIZED)) {
-    if (raw_expr->has_flag(IS_CONST) || raw_expr->has_flag(IS_CONST_EXPR)) {
-      skip = true;
-    } else {
+  } else if (raw_expr->has_flag(IS_CONST) || raw_expr->has_flag(IS_CONST_EXPR)) {
+    skip = true;
+    LOG_TRACE("skip const expr", K(*raw_expr), K(cell_idx));
+  }
+  if (OB_SUCC(ret) && !skip) {
+    if (!raw_expr->has_flag(IS_COLUMNLIZED)) {
       ret = OB_ERR_UNEXPECTED;
       LOG_ERROR("param expr should have be columnlized", K(*raw_expr));
+    } else if (OB_FAIL(idx_provider.get_idx(raw_expr, cell_idx))) {
+      LOG_ERROR("partition by expr should have be columnlized", K(ret), K(*raw_expr));
     }
-  } else if (OB_FAIL(idx_provider.get_idx(raw_expr, cell_idx))) {
-    LOG_ERROR("partition by expr should have be columnlized", K(ret), K(*raw_expr));
-  } else { /* do nothing. */
   }
   return ret;
 }
diff --git a/src/sql/code_generator/ob_expr_generator_impl.cpp b/src/sql/code_generator/ob_expr_generator_impl.cpp
index c960846f0b48d63510cb35e99abb238f768c8fb9..88285eb58184c998c21493b43eee586863369435 100644
--- a/src/sql/code_generator/ob_expr_generator_impl.cpp
+++ b/src/sql/code_generator/ob_expr_generator_impl.cpp
@@ -119,7 +119,7 @@ int ObExprGeneratorImpl::generate_infix_expr(ObRawExpr& raw_expr)
     sql_expr_->start_gen_infix_exr();
     auto& exprs = sql_expr_->get_infix_expr().get_exprs();
     if (OB_FAIL(raw_expr.do_visit(*this))) {
-      LOG_WARN("expr visit failed", K(ret));
+      LOG_WARN("expr visit failed", K(ret), K(raw_expr));
     } else if (exprs.count() > 1) {
       ret = OB_ERR_UNEXPECTED;
       LOG_WARN("should add one expr per visit", K(ret), K(raw_expr));
@@ -1299,6 +1299,7 @@ int ObExprGeneratorImpl::visit(ObCaseOpRawExpr& expr)
 {
   int ret = OB_SUCCESS;
   ObPostExprItem item;
+  bool need_calc = true;
   item.set_accuracy(expr.get_accuracy());
   if (OB_ISNULL(sql_expr_)) {
     ret = OB_ERR_UNEXPECTED;
@@ -1306,14 +1307,26 @@ int ObExprGeneratorImpl::visit(ObCaseOpRawExpr& expr)
   } else if (expr.has_flag(IS_COLUMNLIZED)) {
     int64_t idx = OB_INVALID_INDEX;
     if (OB_FAIL(column_idx_provider_.get_idx(&expr, idx))) {
-      LOG_WARN("get index failed", K(ret));
+      // if an expr has been marked with IS_COLUMNLIZED but get invalid idx,
+      // then it most likely be a const shared expr and need to calculate again
+      if (ret == OB_ENTRY_NOT_EXIST && idx == OB_INVALID_INDEX &&
+          (expr.has_flag(IS_CONST) || expr.has_flag(IS_CONST_EXPR))) {
+        ret = OB_SUCCESS;
+        expr.clear_flag(IS_COLUMNLIZED);
+        LOG_TRACE("need to recalculate const expr", K(expr));
+      } else if (ret != OB_ENTRY_NOT_EXIST) {
+        LOG_WARN("get index failed", K(ret), K(expr), K(idx));
+      }
     } else if (OB_FAIL(item.set_column(idx))) {
       LOG_WARN("failed to set column", K(ret), K(expr));
     } else if (OB_FAIL(sql_expr_->add_expr_item(item, &expr))) {
       LOG_WARN("failed to add expr item", K(ret));
+    } else {
+      need_calc = false;
     }
-  } else {
-    ObExprOperator* op = NULL;
+  }
+  if (OB_SUCC(ret) && need_calc) {
+    ObExprOperator *op = NULL;
     if (OB_FAIL(factory_.alloc(expr.get_expr_type(), op))) {
       LOG_WARN("fail to alloc expr_op", K(ret));
     } else if (OB_UNLIKELY(NULL == op)) {